Monitoring insecticide resistance in house flies (Diptera: Muscidae) from New York dairies

House flies were collected from dairies across New York state and the levels of resistance to seven insecticides were measured using standard laboratory assays with three to five diagnostic concentrations. The highest levels of resistance were found for tetrachlorvinphos, permethrin and cyfluthrin. Although levels of resistance to methomyl were somewhat lower, they were among the highest ever reported for field‐collected house flies. Resistance to pyrethrins was limited primarily to the lowest diagnostic concentration. House flies were susceptible to fipronil at all dairies, suggesting that this material would be highly effective for fly control. The levels of resistance were similar at all the dairies, irrespective of their insecticide use, suggesting substantial movement of flies between facilities. Relative to resistance levels found at New York dairies in 1987, resistance levels had increased for permethrin, were unchanged for tetrachlorvinphos and had decreased for dimethoate. To identify a single diagnostic concentration that could be used in the laboratory assays to assess accurately resistance levels in future studies, we carried out a ‘simulated’ field bioassay using formulated materials. A diagnostic concentration for each insecticide is proposed on the basis of a comparison of our bioassays. © 2001 Society of Chemical Industry     

Chemically induced porphyria: prevention by prior treatment with phenobarbital

The excessive induction of hepatic delta-aminolevulinic acid synthetase in rats after the administration of porphyria-inducing compounds is prevented by prior treatment with phenobarbital. Studies in vivo and in vitro indicate that phenobarbital prevents the induction of chemical porphyria by increasing the rate of detoxification of inducers by way of drug-metabolizing enzymes of the hepatic endoplasmic reticulum.     

Hindsight in marine protected area selection: A comparison of ecological representation arising from opportunistic and systematic approaches

Systematic approaches to site selection for marine protected areas (MPAs) are often favored over opportunistic approaches as a means to meet conservation objectives efficiently. In this study, we compared analytically the conservation value of these two approaches. We locate this study in Danajon Bank, central Philippines, where many MPAs were established opportunistically based on community preference, with few if any contributions from biophysical data. We began by identifying the biophysical data that would have been available when the first MPA was created in Danajon Bank (1995). We next used these data with the reserve selection software Marxan to identify MPAs that covered the same area as is protected under the current set of MPAs (0.32% of the total study area) and that would protect the greatest number of conservation targets at the lowest cost. We finally compared the conservation value of the current MPAs to the value of those selected by Marxan. Because of the dearth of biophysical data available in 1995 and the small area currently under protection, Marxan identified multiple configurations of MPAs that would protect the same percentage of conservation targets, with little differentiation among sites. Further, we discovered that the costs of obtaining and analyzing these data to be used for conservation planning would have been large relative to resources typically available to conservation planners in developing countries. Finally, we found that the current set of MPAs protected more ecological features than would be expected by chance, although not as many as could be protected using a systematic approach. Our results suggest that an opportunistic approach can be a valuable component of conservation planning, especially when biophysical data are sparse and community acceptance is a critical factor affecting the success of an MPA.     

Miocene burrows of extinct bear dogs: indication of early denning behavior of large Mammalian carnivores

Partial skeletons of four species of extinct carnivores have been found in their dens excavated in the floodplain of an early Miocene ephemeral braided stream at Agate Fossil Beds National Monument, Nebraska. Bear dogs (Carnivora: Amphicyonidae) were the principal occupants; their den dimensions and body size are similar to those of living wolves and hyenas. Discovery of this predator community extends the record of denning behavior of large mammalian carnivores to the early Miocene, 20 million years ago.